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Issue
1
Steer Unit Operation
- 4 Wheel Steer Machines
2 Wheel Steer Mode
- Right Turn
The illustration shows the flow through the steering
unit in a right hand turn condition. The operation is
identical to that described for the 4 wheel steer
mod e, exc ep t t he st eer mod e c ont rol valve
X
iscolates the oil flow to the rear power track rod
ram
41
, consiquently the rotor lobes pump oil out
to the front power track rod only. The rear wheels
are held in the straight ahead position by the
locked-up oil in the rear power track rod ram.
Component Key:
A
Inner Spool
B
Outer Spool
D
Stator
LS
Load Sensing Port
X
Steer Mode Control Valve
40
Front Power Track Rod Ram
41
Rear Power Track Rod Ram
43B
Relief Valve
43C
Non-Return Valve
In 2 wheel steer mode the spools of the steer mode
control valve
X
are configured as shown.
4 -
13
4 -
13
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